Diffence between "select count(null)" and "select count(1)"

Posted by Midhat on Stack Overflow See other posts from Stack Overflow or by Midhat
Published on 2010-03-31T10:37:18Z Indexed on 2010/03/31 10:43 UTC
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mysql

In MySQL

Select 1 from mytable

and

select null from mytable

both return the same number of rows. While select count(1) from mytable returns the rowcount and select count(null) from mytable always returns 0. Why?

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Developer IT

Diffence between "select count(null)" and "select count(1)" - Developer IT

Diffence between "select count(null)" and "select count(1)"

mysql

Related posts about mysql

How to remove MySQL completely with config and library files on ubuntu 12.04 gnome 3.0

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Why is there a /etc/init.d/mysql file on this Slackware machine? How could it have gotten there?

mysql: Bind on unix socket: Permission denied

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